docs: def features(self):
          """list: Get the features stored in memory or in the GFF file"""
  
          if self.feature_file:
              log.debug('{}: reading features from feature file {}'.format(self.id, self.feature_path))
              with open(self.feature_path) as handle:
                  feats = list(GFF.parse(handle))
                  if len(feats) > 1:
                      log.warning('Too many sequences in GFF')
                  else:
                      return feats[0].features
  
          else:
              return self._features